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Molarity Formula:
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Molarity (M) is a measure of the concentration of a solute in a solution, expressed as moles of solute per liter of solution. This calculator determines molarity when you know the mass percentage of the solute, the density of the solution, and the molecular weight of the solute.
The calculator uses the formula:
Where:
Explanation: The formula converts mass percentage to molarity by accounting for the density of the solution and the molecular weight of the solute. The factor of 10 converts from percentage (per 100) to per liter (1000 mL) while accounting for density in g/mL.
Details: Molarity is crucial in chemistry for preparing solutions, performing dilutions, and conducting quantitative analyses. It's particularly important in analytical chemistry, biochemistry, and pharmaceutical preparations.
Tips: Enter mass percentage (0-100%), density in g/mL, and molecular weight in g/mol. All values must be positive numbers. The calculator will compute the molarity in mol/L.
Q1: What's the difference between molarity and molality?
A: Molarity is moles per liter of solution, while molality is moles per kilogram of solvent. Molarity changes with temperature (due to density changes), while molality does not.
Q2: Why do we multiply by 10 in the formula?
A: The factor of 10 converts from percentage (per 100) to per liter (1000 mL) while accounting for density in g/mL (1000 mL × 1 g/mL = 1000 g).
Q3: Can I use this for any solute?
A: Yes, as long as you know the mass percentage, solution density, and molecular weight of the solute.
Q4: How accurate is this calculation?
A: The calculation is mathematically exact, but accuracy depends on the precision of your input values.
Q5: What if my solution is very concentrated?
A: For highly concentrated solutions, the relationship between mass% and molarity may become non-linear due to volume changes on mixing.